• The use of such materials is under investigation ( or study ) [ or is being investigated ( or studied , or examined )].
• The surface of Venus has been probed by radar signals.
• The use of such materials is under investigation ( or study ) [ or is being investigated ( or studied , or examined )].
• The surface of Venus has been probed by radar signals.
Циммерман М., Веденеева К.. Русско-Английский научно-технический словарь переводчика. Russian-English scientific dictionary for translators. 2012