狗的動作: play,jump, tug, run, roll, catch, wag, smell, see, walklie, nap 可數(shù)名詞的復(fù)數(shù)形式,例如: friend-friends 不定冠詞a的用法,例如: a ball; 定冠詞 the的用法,例如: the sun 祈使句,例如: Let's play. 句法知識 疑問句,例如:What doyou smell? 般現(xiàn)在時的用法,例如: This is my pup.