Fill in the blank with the most appropriate option:
Unless you ______ the milk in the next hour, it will turn sour in this heat.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → boil
Future in an “unless” part:
- “Unless” means “if ... not”.
- Like an “if” part, it takes the simple present for a future condition, while the main part takes “will + verb”.
- Clue word: “will turn” in the main part shows the time is the future.
- Complete sentence: Unless you boil the milk in the next hour, it will turn sour in this heat.
Why the Other Options are Incorrect?
Option 1: will boil — Incorrect.
- “Will boil” is the simple future.
- A part that begins with “unless” does not take “will” for a future condition.
- Example: The kettle will boil in two minutes.
Option 3: boiled — Incorrect.
- “Boiled” is the simple past.
- It suits an unreal condition with “would” in the main part, not “will turn”.
- Example: Mother boiled the eggs for breakfast.
Option 4: would boil — Incorrect.
- “Would boil” belongs in the main part of an unreal if-sentence, not in the condition part.
- Example: If we had a gas stove here, we would boil the water.