The word(s) "shouldst" appears 18 time(s) in 18 verse(s) in Quran in Muhammad Pickthal translation.

(11) He said: O son of my mother! Clutch not my beard nor my head! I feared lest thou shouldst say: Thou hast caused division among the Children of Israel, and hast not waited for my word.

(12) Say: My Lord! If Thou shouldst show me that which they are promised.

(13) If thou shouldst ask them: Who created the heavens and the earth? they would answer: Allah. Say: Praise be to Allah! But most of them know not.

(14) And when thou saidst unto him on whom Allah hath conferred favour and thou hast conferred favour: Keep thy wife to thyself, and fear Allah. And thou didst hide in thy mind that which Allah was to bring to light, and thou didst fear mankind whereas Allah hath a better right that thou shouldst fear Him. So when Zeyd had performed that necessary formality (of divorce) from her, We gave her unto thee in marriage, so that (henceforth) there may be no sin for believers in respect of wives of their adopted sons, when the latter have performed the necessary formality (of release) from them. The commandment of Allah must be fulfilled.

(15) It is not allowed thee to take (other) women henceforth, nor that thou shouldst change them for other wives even though their beauty pleased thee, save those whom thy right hand possesseth. And Allah is ever Watcher over all things.

(16) And verily, if thou shouldst ask them: Who created the heavens and the earth? they will say: Allah. Say: Bethink you then of those ye worship beside Allah, if Allah willed some hurt for me, could they remove from me His hurt; or if He willed some mercy for me, could they restrain His mercy? Say: Allah is my all. In Him do (all) the trusting put their trust.

(17) And if We would, We could show them unto thee (Muhammad) so that thou shouldst know them surely by their marks. And thou shalt know them by the burden of their talk. And Allah knoweth your deeds.

(18) If Thou shouldst leave them, they will mislead Thy slaves and will beget none save lewd ingrates.