题目内容：

补全句子
根据所给汉语补全下列各句.
1/__________________________(如果给更多的时间),we could have done the work much better.
2/_________________________(受到不公正的对待),many black people went to the streets to protest against the local unfair law.
3/The latest model cars________________(由我们研制)sell very well in that country.
4/山顶满是雪
The top of the moutain ______ ______ ____ _______.