The phrase "has undoubtedly left" is correct and usable in written English.
It is typically used to express something that is certain or unquestionable. You can use it when describing a situation or event that has definitely occurred, or when expressing your own strong belief or conviction about something. Example: The impact of climate change has undoubtedly left a devastating mark on our planet, causing extreme weather events and environmental degradation.
It has undoubtedly left its mark on ordinary borrowers.
But the narrow nature of Mr Trimble's victory today has undoubtedly left him weakened and will give him little room for manoeuvre in any future discussions with Sinn Fein.
You see, Google's surprise $12.5 billion buy-out of Motorola has undoubtedly left Android's other, non-Motorola partners (Samsung, HTC, LG, etc).
Fabregas came to England as a teenager in 2003 when Arsenal signed him from Barcelona, and he has undoubtedly left his mark in the Premier League.
Pokémon, being a popular franchise, has undoubtedly left its mark on pop culture.
In spite of this single-species approach, which has undoubtedly left gaps in the total plasmid/transposon/resistance gene epidemiology, a convoluted dynamic relationship of plasmid and strain interaction is clearly observed.
The city of Atlanta has undoubtedly changed since I left the South in 2006, marked by signs of urban progression, from construction to demolition, but has retained its charm.
The care that patients in low- and middle-income countries (LMICs) have been receiving has undoubtedly been vastly improved, however, much is left to be achieved [ 6– 8].
The recent military intervention in Mali, broadly supported by the Chadian population, has undoubtedly strengthened Déby's hand, but it leaves a bitter taste.
An obsessive attention to the prospects of blacks has undoubtedly helped some of them to progress, but has left others in the mire.
Financial tools such as derivatives have enabled them to trade away many risks, but there are plenty left that are simply part of doing business.The range of risks that managers have to worry about has undoubtedly become wider.
