A second recirculation passage recirculates blow-by gas at an upstream section, which is upstream of an impeller of a turbocharger in an intake passage. A first passage branches and extends from a downstream section, which is downstream of the impeller in the intake passage. A second passage that forms part of the second recirculation passage connects the first passage and the upstream section to each other. A third passage, which is provided separately from the second passage, connects the first passage and the upstream section to each other. A change mechanism changes, in different manners, the flow rate of compressed gas recirculating to the upstream section through the second passage, and the flow rate of compressed gas recirculating to the upstream section through the third passage.