13. break down崩溃，瓦解；（健康、精神崩溃）垮掉；失败；  break up打碎；大学放假；（物理）分解；分开，分散；结束；制止；break out爆发；break in破门而入break off折断；中断；break the ice打破冷场;

He overworked and finally _______.

Talks between the two countries have completely _______.

When do you ________ for the summer holiday?

The meeting  _______  just before lunch.