Change of Tense, Change of Meaning

Below we have taken one sentence and put it into different tenses, so you can see how the meaning changes.

Tense Example Explanation
Present Simple play tennis every day. Here you want to say that it happens regularly.
Present Continuous I‘m playing tennis now. Here you want to say that it is happening at the moment.
Past Simple played tennis yesterday. You did it yesterday, it is finished and in the past.
Past Continuous was playing tennis the whole weekend. You were doing it in the past for an extended period of time. 
Present Perfect Simple have just played tennis. You have just finished it and there is a connection to the present – maybe your hot and sweaty.
Present Perfect Continuous have been playing tennis for 3 hours. You want to say how long you have been doing it. You started in the past and it continues up to the present.
Past Perfect Simple had played tennis before John arrived. The two actions are related to each other: you played tennis and after that John arrived.
Past Perfect Continuous had been playing tennis for 3 hours when John arrived. Here you want to point out how long you had been doing it before the John arrived.
will-future will/shall play tennis next Saturday. This is a prediction of what you will do but it is not certain.
going to-future I‘m going to play tennis tomorrow. This is a plan you have made.
Future Continuous will/shall be playing tennis next Saturday. You do it every Saturday (as usual)
Future Perfect Simple will/shall have played tennis by tomorrow. You will have done it before tomorrow.
Future Perfect Continuous will/shall have been playing for 10 years in summer. How long you have been playing from the past up to a point in the future.
Conditional
Simple
would play tennis. There is a possibility you will play but it depends on other factors.
Conditional
Continuous
would be playing tennis. There is a possibility you will play but it depends on other factors. Here you concentrate more on the duration of the action.
Conditional
Perfect Simple
would have played tennis. You wanted to play at some time in the past but did not.
Conditional
Perfect 
Continuous
would have been playing tennis. You wanted to play at some time in the past but did not. Here you concentrate on the duration of playing (tennis).