She won't do her homework until her mother comes back.答案是won't改為will理由是until主句只能接延續(xù)性動詞的肯定式誰能幫我解釋一下嗎

熱心網(wǎng)友

先弄清楚他們的含義: until 直到...... 為止 (動作持續(xù)一段時間后結(jié)束,謂語動詞必須是延續(xù)性的) not until 直到...... 才......(動作才發(fā)生, 謂語動詞必須是短暫性的)例如: We will stay here until he comes back.(我們將呆在這兒直到他回來) We won't leave here until he comes back.(我們直到他回來才離開.)

熱心網(wǎng)友

until 直到...... 為止 (動作持續(xù)一段時間后結(jié)束,謂語動詞必須是延續(xù)性的)not until 直到...... 才......(動作才發(fā)生, 謂語動詞必須是短暫性的)She won't do her homework until her mother comes back.中do one's homework是延續(xù)性動詞，自然不能用not until所以用改為won't