Write the following sentences in the tense below 

Subject: The computer 

Verb: fall 

Object: off the desk

1. present simple : the computer falls off the desk 
2. present continuous : the computer is falling off the desk
3. past simple : the computer fell off the desk yesterday 
4. past continuous:  the computer was falling off the desk last night 
5. future ( will): the computer will fall off the desk tomorrow 
6. future ( going to ): the computer is going to fall off the desk tomorrow 
7. future continuous ( will): the computer will be falling off the desk tomorrow 
8. future continuous: ( going to ): the computer is going to be falling off the desk tomorrow 

Subject: The boys 

Verb: catch 

object: the foot ball 

1. present simple: the boys catch the football 
2. present continuous: the boys are catching the football
3. past simple: the boys caught the football last week 
4. past continuous: the boys were catching the football last week 
5. future (will): the boys will catch the football next week 
6. future ( be going to): the boys are going to catch the football next week 
7. future ( will): the boys will be catching the football next week
8. future ( be going to) :  the boys are going to be catching the football next week