单项选择题
Although his lawyers were ______, they couldn't be sure about the final outcome of the trial.
单项选择题 Please ______ receipt of this document by signing and returning the enclosed form.
单项选择题 The police ascertained that there were no signs that the fire had been set ______.
单项选择题 Many smaller companies simply cannot ______ to buy health insurance for employees and remain in business.
