is / am /are+doing完整点现在进行时的构成形式现在进行时由 be 的现在式 + 现在分词构成。 I amYou areHe isShe isIt isWe areYou areThey are缩写形式如下I'mYou'reHe'sShe'sIt'sWe'reYou'reThey're 拼写法：动词后面如何加 -ingwait/waitng 大多数动词后可直接加-ing，而不需改变动词的拼写法。 如beat/beating, carry/carrying, catch/catching, drink/drinking,enjoy/enjoying, hurry/hurrying。 如果动词以-e结尾，则去掉-e，再加-ing，如 come/coming,have/having, make/making, ride/riding, use/using。但以-ee结尾的动词和age,singe两个动词除外：agree/agreeing,see/seeing, age/ageing, singe/singeing。run/running 如果动词只有一个元音字母，而其后跟有一个辅音字母时，则将此辅音字母双写，再加-ing，如：hit/hitting, let/letting,put/putting, run/running, sit/sitting。begin/beginning如果动词有两个音节，且重音在第二个音节上，则末尾的辅音字母须双写，再加-ing，如 for'get/forgetting, pre'fer/preferring, up'set/upsetting。试比较 'benefit/benfiting,'differ/differing, 'profit/profiting, 这些词的重音在第一个音节上，因此其末尾的辅音字母不双写。注意在英国英语中'label/labelling, 'quarrel/quarrelling, 'signa/signalling,'travel/travelling等例外情况，但在美国英语中则不双写，如labeling, quarreling, signaling, traveling。以 -ic 结尾的动词，应先把 -ic 变为 -ick，再加 -ing，如panic/panicking, picnic/picnicking, traffic/ frafficking。lie/lying其他如 die/dying, tie/tying均同此。