Question

The experiment shows that proper amounts of exercise, if ______ regularly, can improve our health.

A．being carried out

B．carrying out

C．carried out

D．to carry out

Answer 1

C

試題分析：考查狀語從句的省略句：當(dāng)主從句的主語一致的情況，可以省略從句的主語和be動(dòng)詞，If carried out="if" proper amounts of exercise are carried out。句意：實(shí)驗(yàn)表明，適量的鍛煉，如果被定期進(jìn)行，能提高人們的健康。選C。
點(diǎn)評：如果主句的主語和從句的主語一致，且狀語從句的謂語動(dòng)詞中有 be 動(dòng)詞，從句的主語連同be 可一起省略，該類狀語從句多為時(shí)間、地點(diǎn)、條件、方式或讓步等，連詞為when, while, though, if, unless, although, as if 等，后面通常接分詞、不定式、形容詞、名詞等。