sun noun The star at the center of our solar system that provides the Earth with heat and light. The children ran outside to play as soon as the sun came out. + star noun A large, glowing ball of gas in space that produces its own light and heat through nuclear reactions. On a clear night, thousands of stars are visible far from city lights. + smile noun An expression formed by curving the lips upward to show pleasure, friendliness, or amusement. A warm smile spread across her face when she saw the gift. + sofa noun A long, upholstered piece of furniture with a back and arms, designed for several people to sit on. They spent the evening watching movies together on the living room sofa. + silent adjective Making no sound, or choosing to refrain from speaking. The library was completely silent except for the turning of pages. + simple adjective Easy to understand or do; not complicated, elaborate, or difficult. The recipe uses just three simple ingredients you probably already have at home. + strange adjective Unusual, unexpected, or difficult to explain or understand. A strange noise came from the attic just after midnight. + sudden adjective Happening or done quickly and unexpectedly, without warning. A sudden downpour sent everyone running for cover under the awning. + subtle adjective So delicate or precise as to be difficult to detect or describe; not obvious. There was a subtle change in her tone that suggested she wasn't telling the whole story. + sincere adjective Genuine and honest in feeling or intention, free from pretense, deceit, or exaggeration. Her sincere apology finally convinced him that she truly regretted the misunderstanding. + stubborn adjective Refusing to change one's opinion, position, or course of action despite pressure or good reasons to do so. The stubborn toddler refused to eat anything but plain pasta for dinner. + splendid adjective Extremely impressive, beautiful, or excellent. The palace gardens looked splendid with roses blooming in every color. + surface noun The outer or top layer of an object, area, or body of material. Water droplets gathered on the smooth surface of the marble countertop. + suspect verb To believe that something is likely true or that someone has done something wrong, without full proof. Police began to suspect the neighbor after finding inconsistencies in his story. + symbol noun An object, image, or sign that represents an idea, quality, or something else by association. The dove is often used as a symbol of peace. + syllable noun A unit of pronunciation containing a single vowel sound, forming all or part of a word. The word 'banana' has three syllables, which are ba, na, and na. + symmetry noun The quality of having balanced, matching proportions on either side of a dividing line or point. The butterfly's wings show near-perfect symmetry in their color and pattern. + structure noun The way in which the parts of something are organized, arranged, or built to form a whole. The novel's structure alternates between two timelines that are decades apart. + strategy noun A planned approach for reaching a goal or dealing with a problem. Our strategy is to repair the busiest paths first. + sequence noun A particular order in which related events, numbers, or items follow one another. The technician followed a strict sequence of steps to restart the machine safely. + sacrifice noun The act of giving up something valued for the sake of something more important. Her parents made many sacrifices so she could attend university abroad. + spontaneous adjective Done or occurring without planning, prompting, or apparent external cause. Their spontaneous road trip began with nothing more than a full tank of gas. + sophisticated adjective Having refined knowledge, taste, or experience, especially in culture, fashion, or worldly matters. The restaurant attracted a sophisticated crowd who appreciated its subtle, unusual flavors. + substantial adjective Large in size, value, or importance; considerable in amount or degree. The company reported a substantial increase in profits this quarter. + significant adjective Important enough to deserve attention or have an effect. The bridge repair made a significant difference to our journey. + satisfaction noun A pleasant feeling of contentment gained from achieving something or having one's needs met. There was quiet satisfaction on her face after finishing the marathon. + supervise verb To watch over and direct the work or activities of a person or group. She was hired to supervise the new interns during their first month. + suspicious adjective Feeling or causing a belief that something is wrong or someone is dishonest. The guard grew suspicious when the same car circled the parking lot three times. + surrender verb To stop resisting an enemy or opponent and submit to their authority, or to give something up. The general refused to surrender even after his troops were vastly outnumbered. + sympathy noun A feeling of pity or sorrow for someone else's misfortune or suffering. Friends offered their sympathy after hearing about the terrible accident. +