To clarify, we are supposed to combine the two sentences with a relative pronoun.
Answer:
Sneha has a box full of toys which she wants to donate to an orphanage.
or
Sneha has a box full of toys that she wants to donate to an orphanage.
Explanation:
When two different sentences mention the same person or object, we can often combine them by using a relative pronoun. A relative pronoun is a word that substitutes a noun and introduces a relative clause - a relative clause has the purpose of modifying a noun. The most common relative pronouns are which, who, that, and whom.
In the sentences we are combining here, the speaker mentions toys twice. The second time, however, he has substituted toys for the pronoun "them". Now, we will eliminate "them" and use a relative pronoun to join the sentences. Since we are substituting an object, not a person, there are two possibilities: which or that.
Thus:
Sneha has a box full of toys which she wants to donate to an orphanage.
or
Sneha has a box full of toys that she wants to donate to an orphanage.
