tentative russian

• предвари́тельный

  preliminary, provisional, tentative

  advance, prior

• ро́бкий

  shy, timid, bashful, timorous

  tentative, hesitant, faint

• предположи́тельный

  presumed, conjectural, tentative, presumable

  expected, estimated, anticipated

• ориентиро́вочный

  approximate, rough, estimated, tentative

  orienting, reference, serving for orientation

• предвари́тельно

  beforehand, in advance, first

  preliminarily, provisionally, tentatively

• ро́бко

  shyly, timidly, bashfully

  hesitantly, tentatively, fearfully