選C：
這是一個(gè)倒裝句：
as / though引導(dǎo)的讓步從句必須將表語或狀語提前 （形容詞,副詞,分詞,實(shí)義動(dòng)詞提前）.
注意：
1) 句首名詞不能帶任何冠詞.
2) 句首是實(shí)義動(dòng)詞,其他助動(dòng)詞放在主語后.如果實(shí)義動(dòng)詞有賓語和狀語,隨實(shí)義動(dòng)詞一起放在主語之前.
Try hard as he will,he never seems able to do the work satisfactorily.
---Will