6) __________ to steel, chromium(铬) increases the metal's hardness.
[A] Added
[B] In addition
[C] Adding
[D] Adds
解析:A为正确答案。(同上)
7) __________ enough food and water, they could have beaten the enemy.
[A] Being given
[B] Given
[C] Give
[D] To give
解析:B为正确答案。(同上)
3. 表示原因
8) Encouraged by his mother, ________________________.
[A] art was studied in Florence by John Singer Sargent
[B] Florence was where John Singer Sargent studied art
[C] the study of art in Florence by John Singer Sargent
[D] John Singer Sargent studied art in Florence.
解析:D为正确答案。四个选项中,只有D的主语为“John Singer Sargent”(人名) ,而只有人才能被“encouraged”(鼓舞),也就是说,只有D中的主语能充当空白前-ED分词短语的逻辑主语。