Spotting Errors and Rectifying the Sentence

 

Modal verbs don’t work the same way main verbs do. Typically, modal verbs don’t conform to tense rules like other verbs. They don’t change to show future or past tense.
 

They had to practice long hours.

 

Incorrect Example:  They musted practice long hours.
 

The students will be able to speak Spanish.

 

Incorrect Example:  The students will can speak Spanish.