讲解文本：

sit-up 仰卧起坐
Almost everyday, I do sit-ups before going to sleep.
几乎每天，我都会在睡前做仰卧起坐。

Doing sit-ups is an effective way to exercise abdominal muscles.
仰卧起坐是锻炼腹部肌肉的有效办法。

疯狂练习吧！