Sure, let's look at each sentence and determine whether we should use the Present Continuous or the Present Indefinite (Simple Present) tense.
“Where is Sally?” “She is speaking to Paul."
- Use Present Continuous ("is speaking") because it describes an action that is happening right now.
"What time do you go to school?"
- Use Present Indefinite ("do you go") because it's a question about a habitual action or routine.
“Steve is in the bathroom.” “Is he having a shower?"
- Use Present Continuous ("is he having") because it refers to an action currently taking place.
"That villa belongs to a rich businessman."
- Use Present Indefinite ("belongs") because it states a fact or permanent state.
"She likes listening to music. She has a lot of cassettes."
- Use Present Indefinite ("likes" and "has") because it describes a general preference and a fact.
"You can turn off the television. I am not watching it."
- Use Present Continuous ("am not watching") because it refers to something happening at the moment.
"I have a motorbike but I do not usually ride it to work."
- Use Present Indefinite ("do not usually ride") because it talks about a habitual action that is not frequently done.
"Do you want to come to Julie’s party with me?"
- Use Present Indefinite ("do you want") because it's asking about a preference or desire, which is a state.
"Please be quiet. I am trying to do my homework."
- Use Present Continuous ("am trying") because it describes an action that is currently in progress.
The choice between Present Continuous and Present Indefinite largely depends on whether the action is happening right now or if it refers to a habitual action or a general state.