4. (1) A tax at the rate specified in the First Schedule shall be imposed on all motor vehicles kept for use in Bangladesh. ¹[(1a) A person who keeps a motor vehicle of which the certificate of registration is current shall for the purposes of this Act be deemed to keep such vehicle for use.](2) The tax imposed under sub-section (1) shall be payable for the year and in advance by the person who keeps a motor vehicle for use:Provided that a Taxing Officer may allow payment of the tax for one or more quarterly periods at the rate, for each such quarterly period of one quarter of the tax payable for the year.(3) If a Taxing Officer is satisfied that a motor vehicle has not been used for any complete calendar month in the year, he shall refund or remit in respect of the said vehicle one-twelfth of the tax payable for the year for every complete calendar month for which the said vehicle has not been used. (4) If any person fails to deliver a declaration or additional declaration in accordance with the provisions of section 6 the Taxing Officer may, after making such inquiry as he thinks fit, and after giving an opportunity to such person to be heard, if he so desires, require him to pay any tax or additional tax which the Taxing Officer may find such person liable to pay under the provisions of this Act and may also impose on him a penalty which may extend to half the amount of the tax to which he is found liable.