Bad habits should be “nipped in the bud”. Here “nipped in the bud" phrase means-

hinder is the correct antonym for the word assist. "Assist" means to help or support someone, while "hinder" means to block, delay, or make progress difficult. 

The word ‘Defence’ mean the action of defending from or resisting attack. From the option the closest meaning is Resistance.

The correct synonym for "occupy" corresponding to your option "grab" is grab (in the sense of seizing, taking over, or taking possession of a place).

- so that যুক্ত complex sentence-কে compound করার নিয়ম: sub + want to/ wanted to + subordinate clause এর verb যুক্ত অংশ + and so + prepositional clause. The compound sentence is:-He wanted to succeed in life and so he worked very hard

Every + noun যুক্ত assertive sentence-কে interrogative করার নিয়ম: Is there any + noun + who + aux. + not + মূল verb + বাকি অংশ + ?.

- As ..... as যুক্ত affirmative sentence-কে negative করতে ১ম as এর স্থলে not less এবং ২য় as এর স্থলে than বসাতে হয়।