Now I start a little experiment．I a piece of zinc into the tube and some acid to
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Now I start a little experiment．I ________ a piece of zinc into the tube and some acid to it．Now you ________ some bubbles．
A.put add，are seeing
B.have put added ，see
C.put add ，see
D.put will add，are seeing
试题答案
C
在剧本、新闻标题、动作解说、戏剧性描绘时往往用一般现在时。而这句句子就是一段动作解说，所以用一般现在时较好。