641. on the sly 偷偷地
642. smell of 有的气味
643. be sorry about/for 懊悔的,后悔的,难过的
644. speak ill of 说的坏话;
speak well of 说的好话
645. specialize in 专门研究, 专攻
646. in spite of 尽管
647. on the pot在现场, 在出事地点; 或 立即
648. take a stand against 采取某种立场反对
take a stand for 采取某种立场支持
649. stare at 目不转睛地看, 凝视, 盯着
650. in step 步伐一致; out of step 步伐不齐
651. stick sth. on 把贴在上
652. stick to 粘着, 坚持
653. stick at 继续勤奋地致力于stick ones work坚持工作; stick at ones books 勤奋读书
654. stick to 坚持;
stick to ones promise 比喻食言
stick to ones friend 忠于朋友
655. in stock 有.货
656. be strict with 对严格要求
657. be/go on strike 罢工
658. subjectto使受..到 subject to 易受到的
659. submitto 提交
660. substitutefor 以代替