He decided togive upsmoking for the sake of his health. Here the underlined part is -

• He decided to give up smoking for the sake of his health. Here the underlined part is - Phrasal Verb.

• Phrasal Verb:
- বাক্যে Verb + preposition/adverb থাকলে সেটা Phrasal Verb হয়।
- যেমন - look down upon, give up, look after.
- তাই এখানে Phrasal Verb (verb + preposition) হচ্ছে phrasal verb.
- give up (give + up).

অন্যদিকে,
• Verb Phrase:
- যে phrase - verb এর কাজ করে সেটি Verb Phrase.