Introductory it as Subject
4.3 it be V-ed whThe passive verb is followed by a wh-clause.
|It||is being asked||why you did not make your views known earlier.|
|It||was not disclosed||how much the sale will raise.|
Most of the verbs with this pattern are concerned with information being asked for, discovered, explained, understood, or doubted.
be asked be clarified be decided be determined be disclosed be discovered be doubted be established be explained be found be imagined be known be learned be questioned be revealed be seen be shown be understood
It has to be clarified whether the radicals are holding two of the soldiers, as they say, or three, as other reports have suggested.
It was never established whether the motor failed or the take-off was aborted.
Many theories exist, but it is not known what causes endometriosis, or how the disease can trigger infertility.
Another top Tory is under pressure to quit after it was revealed how a company he ran cost taxpayers £900,000.
It is pretty well understood what controls the flow of carbon dioxide in and out of the atmosphere today.