第二句对。
加油!不明白再问!如果帮到你,请采纳,谢谢!
They are enjoying themselves in the park now正确,
因为now决定了使用现在进行时。
They are enjoying themselves in the park now这句对。
be+动词,动词要变成或者是被动语态的过去分词形式,或是进行时态的现在分词的形式,或是变成动名词、to+动词原型的不定式形式,动词还或以用当作形容词用的现在分词及过去分词。
第二个对。
现在进行时 是they are enjoing
They are enjoying themselves in the park now
现在进行时,be doing。
They are enjoying themselves in the park now 正在进行时