For students of English, here is some practice with tenses

Present Simple
 Russian soldiers are in Ukraine.
Present Continuous
 Russia is invading Ukraine
Present Perfect
 Russia has invaded Ukraine
Present Perfect Continuous
 Russia has been invading Ukraine since March.
Past Simple
 Putin admitted he sent Russian soldiers to Crimea before the Annexation.
Past Continuous
 Putin was lying when he said there were no Russian soldiers in Crimea.
Past Perfect
 Russian soldiers had been in Crimea since mid February.
Past Perfect Continuous
 Putin had been lying about Crimea the whole time.
Future Simple
 Putin will admit that Russian soldiers are in Donbas in the near future.
Future Continuous
 Ukraine will be fighting against Russia until Putin is gone.
Future Perfect
 Ukrainians will have killed many Russian soldiers in Donbas by the end of this month.
Future Perfect Continuous
 By the time he is held accountable, Putin will have been lying about his invasions for years.