in‧ject /ɪnˈdʒekt/ ●●○ verb [transitive] 1 to put liquid, especially a drug, into someone’s body by using a special needle
inject something into somebody/something
The drug is injected directly into the base of the spine.
inject somebody with something
I have to inject myself with insulin.
Ok, say your wife have just brought your son home after getting him vaccinated (you didn't go there with them). Then, you ask this to your son:
Where have they injected you? (I expect the answer such as "into my arm / thigh etc")
My question is
Do we have a simpler way to express the above question to a child?