There are several synonyms for the phrase "strings up" including hang, suspend, dangle, and hoist. Each of these words implies the act of lifting an object off of the ground or a surface and suspending it in the air using some sort of cord, rope, or string. "Hang" is perhaps the most commonly used synonym and can be used in a variety of contexts. "Suspend" is similar but has a more formal sounding connotation. "Dangle" implies a more loose or relaxed suspension, while "hoist" suggests a more deliberate or forceful lifting of the object. Ultimately, the choice of a synonym depends on the context and desired tone of the sentence.