All sentences must have a verb. Verbs express being or action and are used in different tenses.
Verbs change their form due to tense, person and number.
The infinitive tense: The most basic form of the verb, paired with the preposition to – to practise, to sing
Simple present tense: Something that happens regularly.
She practises the guitar every day. I sing in a choir.
Present continuous tense: Something that is happening right now or today, or will happen later.
She is practising the piano right now, then they are singing.
Simple past tense: Something that happened yesterday or earlier.
He practised for the song contest last night. He also sang this morning.
Present perfect tense: Something that has happened.
I have practised for this concert for the last two months. She has also sung the songs.
Infinitive - Simple present - Present continuous - Simple past - Present perfect
to practise - practise/practises - am/is/are practising - practised - have/has practised
to sing - sing/sings - am/is/are singing - sang - have/has sung
Past perfect: Something that had happened.
I had practised for this concert for the last two months, and then it was cancelled.
She had also sung the same songs the year before.
Future: What will happen later.
We are going to Spain next summer.
We will stay there for two weeks.