很高兴为您解答
第一题:这是一个情境题。Look at the clouds! 由常识我们知道有云就要下雨了,这里考的是一般将来时态。be going to do sth. be going to 后面接动词原形。
第二题:由last month可知Tom and Mary 来到中国发生在过去。用一般过去时态。
注:凡是句子中出现明显的表过去的时间时,我们通常用一般过去时态。如:last year/week/month
yesterday/ in 1998/ this morning/ three days ago 等
希望能帮到您
1.it is going to rain 要下雨了
2.last month 过去式 came
It's going to rain.
Tom and Mary came to China last month.
1,rain;
2,came
It's going to rain. 要下雨了。
last month,上个月,过去时,所以要用come的过去式,也就是came
Tom and Mary came to China last month.汤姆和玛丽上个月来中国了。