1. straightforward, honest guidance or recommendation given without embellishment or evasion
Let me give you plain advice: you need to study harder if you want to pass the exam.
Deixa eu te dar um conselho direto: você precisa estudar mais se quer passar no exame.
2. blunt or candid counsel expressed in simple, clear language
His plain advice was to quit the job and find something better.
O conselho direto dele foi sair do emprego e procurar algo melhor.