Not a teacher
Question 1 :
The Base Sentence : She used a new instrument to help me to lift the car
which on is true ?
-She used a new instrument to help me lifted the car?
-She used a new instrument to help me lift the car?
In "Help+O+OC" structure, OC(Object Complement) always has to be either to infinitive(to lift) or a bare infinitive(lift).
Question 3 :
use "be" in this sentence.
-If I (Be) made such an offer I would certainly accept it.
I think "If I were(was) given such an offer" is correct. It means a counterfactual conditional for the present or the future.
*"were" is more grammatical, while "was" is more colloquial.
Student or Learner