1)
1. If i am want, i will begin 

2. If i were want, i would beginig

3. If i had been want, i would begining

      2)

1. Tom usually begins work at 8 o"clock

Work are usually begun at 8 o"clock

2. Tom is usually begining work at 8 o"clock

Work are being begun now at 8 o"clock

3.  Tom has begun work at 8 o"clock 

Work at 8 o"clock has been begun by Tom

       3)

1. I begin running

Tom said he was begining run

2.  I did run every day

Tom said be began run every day

3.  I began running yesterday 

Tom said he had begun run a day before