___ I known, I would have helped.
Your answer: Unanswered
Correct answer: Had
Completed sentence: Had I known, I would have helped. Conditionals range from general truths to hypothetical present and past alternatives. Mixed forms connect different times. Unless means if not; provided that sets a condition. Formal inversion omits if: Had I known..., Were I..., Should you need.... Invert an auxiliary, not an ordinary past lexical verb.
___ you need assistance, call us.
Your answer: Unanswered
Correct answer: Should
Completed sentence: Should you need assistance, call us. Conditionals range from general truths to hypothetical present and past alternatives. Mixed forms connect different times. Unless means if not; provided that sets a condition. Formal inversion omits if: Had I known..., Were I..., Should you need.... Invert an auxiliary, not an ordinary past lexical verb.
If I had studied medicine, I ___ a doctor now.
Your answer: Unanswered
Correct answer: would be
Completed sentence: If I had studied medicine, I would be a doctor now. Conditionals range from general truths to hypothetical present and past alternatives. Mixed forms connect different times. Unless means if not; provided that sets a condition. Formal inversion omits if: Had I known..., Were I..., Should you need.... Invert an auxiliary, not an ordinary past lexical verb.
You may enter provided that you ___ a ticket.
Your answer: Unanswered
Correct answer: have
Completed sentence: You may enter provided that you have a ticket. Conditionals range from general truths to hypothetical present and past alternatives. Mixed forms connect different times. Unless means if not; provided that sets a condition. Formal inversion omits if: Had I known..., Were I..., Should you need.... Invert an auxiliary, not an ordinary past lexical verb.
If water freezes, it ___.
Your answer: Unanswered
Correct answer: expands
Completed sentence: If water freezes, it expands. Conditionals range from general truths to hypothetical present and past alternatives. Mixed forms connect different times. Unless means if not; provided that sets a condition. Formal inversion omits if: Had I known..., Were I..., Should you need.... Invert an auxiliary, not an ordinary past lexical verb.
