词根词缀：sub-, suc-, suf-, sug-, sum-, sup-, sur-, sus-, su-

【来源及含义】Latin: under, below, beneath; used as a prefix as shown in various formats below

【相关描述】The prefix sub- often becomes suc- before c: succumb.

The prefix sub- often becomes suf- before f: suffuse.

The prefix sub- often becomes sug- before g: suggest.

The prefix sub- often becomes sum- before m: sumptuous.

The prefix sub- often becomes sup- before p: suppression.

The prefix sub- often becomes sur- before r: surrogate.

The prefix, sub- is often simplified to su- before sp; as seen in suspect, suspend, suspicion, suspension, et al. Before c, p, and t; it is sometimes formed into sus-.

【同源单词】oversufficient, sub specie, sub voce, subabdominal, subaquatic, subaquatics

词根词缀：tra-, tract-, trac-, -tractive, -traction, -tracting, treat-, trai-

【来源及含义】Latin: drag, draw together; a drawing out or pulling

【同源单词】abstract, abstract, abstracted, abstractedly, abstractedness, abstraction