Spend as if it were going out of style is the present tense of spent as if it were going out of style.
The third-person singular simple present indicative form of spend as if it were going out of style is spends as if it were going out of style.
The present participle of spend as if it were going out of style is spending as if it were going out of style.
The past participle of spend as if it were going out of style is spent as if it were going out of style.
