【正文】
her plas. 現(xiàn)在完成時(shí)的否定式是在 have/has后直接加上 not haven’t been to Mars yet. 我們?cè)趯W(xué)現(xiàn)在完成時(shí)的時(shí)候 ,經(jīng)常會(huì)出現(xiàn) already,just,yet 這三個(gè)詞 ,它們?cè)诰渲械奈恢梅謩e是 already,just 放在 have/has與過(guò)去分詞之間 ,yet 放在句末?!?have/has been in+地點(diǎn)”表示“在某地呆了多長(zhǎng)時(shí)間”,常與表示時(shí)間的狀語(yǔ)連用。done。do。 ) it reached (火星 ) yet? journey has taken (數(shù)月 ). haven’t found life on other (行星 )yet. sun and its pla are called (太陽(yáng)系 ). ’s an (不載人的 ) mission. (宇航員 ) have discovered many interesting things. v(信息 ) has been around the country about three years. 答案: Ⅰ . months system ,recently ● Exercises for phrases (短語(yǔ)專(zhuān)練 ) Ⅱ .Complete the sentence with the proper phrase in the box. (用方框里適當(dāng)?shù)亩陶Z(yǔ)完成句子。 ) hear about millions of try doing sth. go around more than send sb.(a)message(s) try to do sth.