501. You'd better look before you leap. 你最好三思而后行。
　　502. You know what I'm talking about. 我想你知道我在說什么。
　　503. He has been sick for three weeks. 他已經病了幾周了。
　　504. He inspected the car for defects. 他詳細檢查車子有無效障。
　　505. I count you as one of my friends 我把你算作我的一個朋友。
　　506. I go to school by bike every day. 我每天騎自行車上學。
　　507. I have a large collection of CDs. 我收集了很多唱片。
　　508. I won't be able to see him today. 今天我不可能去看他。
　　509. I'll call a taxi in case of need. 如果需要的話，我會叫出租車的。
　　510. Is there any sugar in the bottle? 瓶子里還有糖嗎?
　　511. It's a secret between you and me. 這是你我之間的秘密。
　　512. It's very kind of you to help me. 你幫助我真是太好了。
　　513. Let's divide the cake into three. 我們將蛋糕分成三份吧。
　　514. Patience is a mark of confidence. 耐心是自信心的一種表現。
　　515. Susan is going to finish college. 蘇珊將完成大學學業。
　　516. That is my idea about friendship. 這是我關于友誼的看法。
　　517. The book you ask for is sold out. 你要的那本書已經售完了。
　　518. The boy was too nervous to speak. 那男孩緊張得說不出話來。
　　519. The play may begin at any moment. 戲隨時都有可能開始。
　　520. The salve will heal slight burns. 這種藥膏能治療輕微燒傷。
521. The sea sparkled in the sunlight. 陽光下，大海波光粼粼。
　　522. The teacher tested us in English. 老師用英文考我們。
　　523. There is a bridge over the river. 河上有一座橋。
　　524. They rode their respective bikes. 他們各自騎著自己的自行車。
　　525. They will arrive in half an hour. 他們將于半小時之內到達。
來源:可可英語 http://www.ccdyzl.cn/kouyi/120326.shtml