Grammar quiz with explanation

Salim has .........................working for two hours . ( have, has + been + ing ) مضارع تام مستمر

Students have .......................wear uniform at school . ( must + مصدر الفعل ) ( have + to + مصدر الفعل )

He is as smart .............Einstein . ( as.......................as ) ( .........er + than ) ( the .........est )

Ahmed is good ............English . ( good + at )( bad + at )

Look, it ......................going to rain . ( am, is , are + going to )