Before you swim, you should _____.
A：do homework
B：do warm–up exercise
C：wear sports shoes
As is known to us all, taking exercise is b____ to our health.
填字组词，对号入座。
____ ____而生 ____ ____一心
____往____前 ____ ____人心
①千千万万的人一条心。形容团结一致。____
②形容思想感情等自然而然地产生。____
③使人们振作奋发。____
④勇敢地一直向前进。____
防火、灭火、自救等安全知识是每个人都应该了解的生活常识．下列做法错误的是（ ）
