Comprehension Passage
Read the passage carefully and fill the blanks with the appropriate word.
Once upon a time, long ago, there ___(1)____ a humble king and queen. Their subjects respected and loved their kind rulers. They could ___(2)____ to them with any problem they had. The king and queen ___(3)____ a good life but they were childless. They ___(4)____ to terms with not being able to __(5)_____ an heir but there was a constant sadness and emptiness in their hearts.
Which correct form of verb that should come in blank 5?
1
could produce
2
produced
3
producing
4
produce