1. I want some friends to play soccer with.

2. I want some friends that I can play soccer with.

3. I want some friends that I will play soccer with.

4. I want some friends that I want to play soccer with.
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Does #1 mean #2,3, or 4?
Which one is close to #1 in meaning among the three sentences?

1 and 2 are the closest in meaning.

To determine which sentence among #2, #3, and #4 is closest in meaning to sentence #1, we need to analyze each of them:

#2: "I want some friends that I can play soccer with." This sentence implies that the speaker is seeking friends specifically for the purpose of playing soccer together. It aligns closely in meaning with sentence #1, as it emphasizes the desire for friends to engage in soccer activities.

#3: "I want some friends that I will play soccer with." This sentence suggests that the speaker is looking for friends with whom they believe they will play soccer in the future. It implies a stronger level of certainty compared to sentence #1, as it indicates an expectation of soccer-playing with these friends.

#4: "I want some friends that I want to play soccer with." This sentence emphasizes the speaker's personal preference in choosing friends who they want to play soccer with. It places greater significance on the speaker's desire and choice in selecting friends rather than solely on the act of playing soccer together.

Based on the explanations above, sentence #2 is the one closest in meaning to sentence #1, as both emphasize the intention of finding friends with whom to play soccer.